Copper oxide (also referred to as cupric oxide, CuO) has a range of commercial uses, including as a reactant in analytical chemistry, in electroplating processes, in the purification of hydrogen, as a pigment in glass, ceramic, and porcelain enamels, and as a precursor to a number of copper (II) salts. One of the largest commercial applications of copper oxide is in the production of wood preservatives, including chromated copper arsenate (CCA).